NOISE REDUCING DEVICE, AND JET PROPULSION SYSTEM

摘要

Provided is a noise reducing device in a jet engine, which comprises a cylindrical casing, a cylindrical partition inserted in the casing while protruding partially from the trailing edge of the casing, and a compressor for compressing air introduced into the inside of the cylindrical partition. The inside of the cylindrical partition is used as a passage, in which the core stream of high speed air flows, and the space between the cylindrical partition and the casing is used as a passage, in which the bypass stream of low speed air flows. The noise reducing device is connected to the wing of an airplane by a pylon having a protrusion protruding downstream over the casing to the downstream sides of the core stream and the bypass stream. The noise reducing device further comprises a nozzle, which is disposed at the pylon on the downstream side of the core stream, for injecting a fluid toward a noise generating source to appear when an external stream established outside of the bypass stream and the core stream approach each other.